The fleshy fibres on each side of this opening act as a sphincter. | east the Yeni Kapu or new gate. A citadel enclosure stands Passing between the xiphoid and costal origins in front are the at the N. E. corner and is now partly in ruins, but the interior superior epigastric arteries, while the other terminal branches of space is occupied by the government konak. The summer the internal mammaries, the musculo-phrenics, pass through climate in the confined space within the town is excessively hot between two costal origins.

and unhealthy. Epidemics of typhus are not unknown, as well Through the crura pass the splanchnic nerves, and in addition as ophthalmia. The Diarbekr boil is like the "Aleppo button," to these the left crus is pierced by the vena azygos minor. The lasting a long time and kaving a deep scar. Winters are fresympathetic nerves usually enter the abdomen behind the internal quently severe but do not last long. Snow sometimes lies, and arcuate ligaments. The phrenic nerves, which are the main ice is stored for summer use. Scorpions noted for the virulence of supply of the diaphragm, divide before reaching the muscle and their poison abound as well as horse leeches in the tanks. The pierce it in a number of places to enter its abdominal surface, but town is supplied with water both by springs inside the town some of the lower intercostal nerves assist in the supply. The last and by aqueducts from fountains at Ali Punar and Hamervat. thoracic or subcostal nerves pass behind the external arcuate The principal exports are woul, mohair and copper ore, and ligament

imports are cotton and woollen goods, indigo, coffee, sugar, For the action of the diaphragm sce RESPIRATORY SYSTEM. petroleum, &c. Embryology.-The diaphragm is at first developed inthe neckregion

The Great Mosque, l'lu Jami, formerly a Christian church, of the embryo, and this accounts for the phrenic nerves, which supply occupies the site of a Sassanian palace and was built with it. rising from the fourth and fifth cervical. From the mesoderm on materials from an older palace, probably that of Tigranes II. and in this the central tendon is formed. The fleshy portion"i: The remains consist of the façades of two palaces 400 ft. apart, developed on each side in two parts, an anterior or sterno-costal each formed by a row of Corinthian columns surmounted by an shich is derived from the longitudinal neck musculature, probably equal number of a Byzantine type. Kufic inscriptions run across the uume layer from which the sternothyroid comes, and a spinal part the fronts under the

entablature. The court of the mosque which is a derivative of the transversalis sheet of the trunk. Between is entered by a gateway on which lions and other animals are is obliterated by the growth of the pleuro-peritoneal membrane, which sculpturel. The churches of greatest interest are those of SS. may occasionally fail to close and so may form the site of a phrenic Cosmas and Damian Jacobitc) and the church of St James bernia. With the growth of the body and the development of the (Grech). In the 19th century Diarbekr was one of the largest lungs the diaphragm shifts its

position until it becomes the septum and most flourishing cities of Asia, and as a commercial centre it A. Paterson has recorded cases in which the left hall of the diaphragm is at the head of the navigation of the Tigris, which

is traversed Development of the Diaphragm," Jour. of Anal. and Phys. vol. 39.5 now stands at the meeting-point of several important routes. It is wanting (Proceedings of the Anatomical Society of Gt. Britain, down stream by keleks or rasts supported by inflated skins. June 1900; Jour. Of Anal. and Phys. vol. 34), and occasionally There is a good road to Aleppo and Alexandretta on the Mediterdeficiencies are found elsewhere, especially in the sternal portion.ranean, and to Samsun on the Black Sea by Kharput, Malatia

Comparative Anatomy -A complete diaphragm, separating the and Sivas. There are also routes to Mosul and Bitlis. thoracic from the abdominal parts of the coelum, is characteristic of Diarbekr became a Roman colony in A.D. 230 under the name the Mammalia; it usually has the human structure and relations of Amida, and received a Christian bishop in A.D. 325. It was by the azygous lobe of the lung. In some Mammals, 2.2. Echidna enlarged and strengthened by Constantius II., in whose reign it and Phorvena, it is entirely muscular. In the Cetacea it is remarkable was taken after a long siege by Shapur (Sapor) II., king of Persia. for its obliquity; its vertebral attachment is much nearer the tail The historian Ammianus Marcellinus, who took part in the than its sternal or ventral one; this allows a much larger lung space defence, gives a detailed account of it. In the later wars between in the dorsal than in the ventral part of the thorax, and inay be the Persians and Romans it more than once changed hands. suchungen uber die Veränderung, welche die Respirationsorgane der Though ceded by Jovian to the Persians it again became annexed Saugetiere durch die Anpassung an das Leben im Wasser erlitten to the Roman empire, and in the reign of Anastasius (A.D. 502) haben," Jen. Zeitschr. S. Valuruiss., 1848. p. 93.). In the l'ngulata was once more taken by the Persians, when 80,000 of its inl'ngulata." Proc. Zool. Soc., 1903, p. 287). Below the Mammals habitants were slain. It was taken c. 638 by the Arabs, and incomplete partitions betwecn the pleural and peritoneal cavities afterwards passed into the hands of the Seljuks and Persians, are found in Chelonians, Crocodiles and Bırds, and also in Amphibians from whom it was finally captured by Selim I. in 1575; and (Xenopus and Pipa).

(F. G. P.) since that date it has remained under Oltoman rule. About a m. DIARBEKR (Kara Amid or Black Amid; the Roman below the town is a masonry bridge over the Tigris; the older Amida), the chic town of a vilayet of Asiatic Turkey, situated portion being probably Roman, and the western part, which bears on a basaltic plateau on the right bank of the Tigris, which here a Kufic inscription, being Arab. flows in a deep open valley. The town is still surrounded by the I he vilayet of Diarbekr extends south from Palu on the masonry walls of black basalt which give it the name of Kurs Euphratesto Mardinand Sisibin on the edge of the Mesopotamian or Black Amid; they are well built and imposing on the west plain, and is divided into three sanjaks-Arghana, Diarbekr and lacing the open country, but almost in ruins where they overlook Mardin. The beadwaters of the main arm of the Tigris have the river. A mass of gardens and orchards cover the slope down the ir svurce in the vilayet. to the river on the S.W., but there are no suburbs outside the Cercals,cotton, tobacco, rice and silk are produced, but most of walls. The houses are rather crowded but only partially fill the fertile lands have been abandoned to semi-nomads, who raise the walled area. The population numbers 38,000, nearly ball large quantities of live stock. The richest portion of the vilayet being Christian, comprising Turks, Kurds, Arabs, Turkumans, lics cast of the capital in the rolling plains watered by tributaries Armenians, Chaldeans, Jacobites and a few Greeks. The streets of the Tigris. An exceptionally nch copper mine exists at are 10 ft to 15 ft. wide, badly paved and dirty; the houses and Arghana Maden, but it is very imperfectly worked; galena shops are low, mostly of stone, and some of stone and mud. mineral oil and silicious sand are also found. The bazaar is a good one, and gold and silver filigree work is

( W. W.; F. R. M.) made, peculiar in character and design. The cotton industry is DIARRHOEA (from Gr. Buá, through, bow, flow), an exces. declining, but manufacture of silk is increasing. Fruit is goud and sive looseness of the bowels, a synpitum of irritation which abundant as the rich volcanic suil is well watered from the town may be due in variuus causes, or may le associated with springs. The size of the melons is specially famous. To the some specific disease. The treatment in such latter cases south, the walls are some 40 ft. high, faced with large cut stone necessarily varies, since the symptom itself may be remedial, blocks of very solid construction, with lowers and square bastions but in onlinary cases depends on the renoval of the cause of rising to 500 ft. There are four gates: on the north the Kharput irritation by the use of aperaents, various slatives being also gate, on the west the Rum, on the south the Mardin, and on the pres ribed. In chronic diarrhoea careful attenlun to the diet is

From Diar, land, and Bekr (ic. Abu Bekr, the caliph). necessary.

of the mines between 1638 and 1665 as a dealer in precious stones. The diamond here occurs in river gravels and sands associated with According to his description shallow pits were sunk, and the grave the same minerals as in Minas Geraes : since 1844 the richest mines excavated was gathered into a walled enclosure where it was crushed have been worked in the Serra de Cincora, where the mountains are and water was poured over it, and it was finally sisted in baskets and intersected by the river Paraguassu and its tributaries; it is said sorted by hand. The buying and selling was at that period conducted that there were as many as 20,000 miners working here in 1845. and by young children. In more modern times there has been the same it was estimated that 54,000 carats were produced in Bahia in 1858. excavation of shallow pits, and sluicing, sifting and sorting, by hand The earlier workings were in the Serra de Chapada to the N.W. of labour, the only machinery used being chain pumps made of earthen the mines just mentioned. In 1901 there were about 5000 negroes bowls to remove the water from the deeper pits.

employed in the Bahia mines; methods were still primitive; the At some of the Indian localities spasmodic mining has been carried cascalho was dug out from the river beds or tunnelled out from the on at different periods for centuries, at some the work which had been valley side, and washed once a week in sluices of running water, long abandoned was revived in recent times, at others it has long been where it was turned over with the hoe, and finally washed in wooden abandoned altogether. Many of the large stones of antiquity were basins and picked over by hand; sometimes also the diamantiferous probably found in the Kollar group, where Tavernier found 60,000 material is scooped out of the bed of the shallow rivers by divers, and workers in 1645 (?), the mines having, according to native accounts, by men working under water in caissons. It is almost exclusively in been discovered about 100 years previously. Golconda was the the mines of Bahia, and in particular in the Cincora district, that the fortress and the market for the diamond industry at this group of valuable carbonado is found. The carbonado and the diamond have mines, and so gave its name to them. The old

mines have now been been traced to an extensive hard conglomerate which occurs in the completely abandoned, but in 1891 about 1000 carats were being middle of the sandstone formation. Diamonds are also mined an raised annually in the neighbourhood of Hyderabad. The Sambalpur Salobro on the river Pardo not far inland from the port of Canavieras group appear to have been the most ancient mines of all, but they in the S.E. corner of Bahia. The enormous development of the South were not worked later than 1850. The Panna group were the most Africanmines, which supplied in 1906, about 90%of the world's produce, productive during the 19th century. India was no doubt the source has thrown into the shade the Brazilian production; but the Bulletin of all the large stones of antiquity: a stone of 671 carats was found for Feb. 1909 of the International Bureau of American Republics gave at Wajra Karur in the Chennur group in 1881, and one of 2104 a very confident account of its future, under improved methods. carats at Hira Khund in 1809. Other Indian localities besides those South Africa. The first discovery was made in 1867 by Dr W. G. mentioned above are Simla, in the N.W. Provinces, where a few Atherstone, who identified as diamond a pebble obtained from a stones have been found, and a district on the Gouel and the Sunk child in a farm on the banks of the Orange river and brought by a rivers in Bengal, which V. Ball has identified with the Soumel pour trader to Grahamstown; it was bought for £500 and displayed in the mentioned by Tavernier. The mines of Golconda and Kurnool were Paris Exhibition of that year. In 1869 a stone weighing 831 carats described as early as 1677 in the twelfth volume of the Philosophical was found near the Orange river; this was purchased by the earl Transactions of the Royal Society. At the present time very few of Dudley for £25,000 and became famous as the “Star of South Indian diamonds find their way out of the country, and, so far as Africa." 'A rush of prospectors at once took place to the banks of the world's supply is concerned, Indian mining of diamonds may be the Orange and Vaal rivers, and resulted in considerable

discoveries, so considered extinct. The first blow to this industry was the discovery that in 1870 there was a mining camp of no less than 10,000 persons of the Brazilian mines in Minas Geraes and Bahia.

on the River Diggings." In the River Diggings the mining was Brasil.-Diamonds were found about 1725 at Tejuco (now Dia- carried on in the coarse river gravels, and by the methods of the mantina) in Minas Geracs, and the mining became important about Brazilian negroes and of gold placer-miners. A diggers' committee side of the Serra da Mata da Corda (2) Rio Abaete on the E. side of bank; the sgravel clang sandalere quase quith free access to the river the same range; these two districts being among the head waters of screens of perforated metal, and the concentrates were sorted by the Rio de San Francisco and its tributaries; (3) Diamantina, on and hand on tables by means of an iron scraper. about the watershed separating the Rio de San Francisco from the But towards the close of 1870 stones were found at Jagersfontein Rio Jequitinhonha; and (4) Grao Mogul, nearly 200 m. to the N.E. and at Dutoitspan, far from the Vaal river, and led to a second

great of Diamantina on the latter river.

rush of prospectors, especially to Dutoitspan, and in 1871 to what The Rio Abaete district was worked on a considerable scale between is now the Kimberley mine in the neighbourhood of the latter. At 1785

and 1807, but is now abandoned. Diamantina is at present the each of these spots the diamantiferous area was a roughly circular most important district; it occupies a mountainous plateau, and patch of considerable size, and in some occupied the position of the diamonds are found both on the plateau and in the river valleys one of those depressions or "pans" so frequent in S. Africa. These below it. The mountains consist here of an ancient laminated dry diggings were therefore at first supposed to be alluvial in origin micaceous quartzite, which is in parts a flexible sandstone known as like the river gravels; but it was soon discovered that, below the red itacolumite, and in parts a conglomerate; it is interbedded with surface soil and the underlying calcareous deposit, diamonds were also clay-slate, mica-schist, hornblende-schist and haematite-schist, and found in a layer of yellowish clay about 50 ft. thick known as "yellow intersected by veins of quartz. This series is overlain unconformably ground." Below this again was a hard bluish-green serpentinous rock by a younger quartzite of similar character, and itself rests upon the which was at first supposed to be barren bed-rock; but this also crystalline schists. The diamond is found under three conditions: contained the precious stone, and has become famous, under the (1) in the gravels of the present rivers, embedded in a ferruginous clay: name of " blue ground," as the matrix of the S. African diamonds. cemented conglomerate known as cascalho; (2) in terraces (gupiarras) The yellow ground is merely decomposed blue ground. In the in a similar conglomerate occupying higher levels in the present Kimberley district five of these round patches of blue ground were valleys; (3) in plateau deposits in a coarse surface conglomerate found within an area little more than 3 m. in diameter; that at known as gurgulho, the diamond and other heavy minerals being Kimberley occupying to acres, that at Putoitspan 23 acres. There embedded in the red clay which cements the larger blocks. Under were soon 50,000 workers on this field, the canvas camp was replaced all these three conditions the diamond is associated with fragments by a town of brick and iron surrounded by the wooden huts of the of the rocks of the country and the minerals derived from them, natives, and Kimberley became an important centre. especially quartz, hornstone, jasper, the polymorphous oxide of It was soon found that each mine was in reality a huge vertical titanium (rutile, anatase and brookite), oxides and hydrates of iron funnel or crater descending to an unknown depth, and hiled with (magnetite, ilmenite, haematite, limonite), oxide of tin, iron pyrites, diamantiferous blue ground. At first each claim was an independent tourmaline, garnet, xenotime, monazite, kyanite, diaspore, sphene, pit 31 st. square sunk into the blue ground; the diamantilerous rock topaz, and several phosphates, and also gold. Since the heavy I was

hoisted by bucket and windlass, and roadways were lelt across minerals of the cascalho in the river beds are more worn than those of the pit to provide access to the claims. But the roadways sonn lell the terraces, it is highly probable that they have been derived by the in, and ultimately haulage from the claims could only be provided by cutting down of the older river gravels represented by the terraces: means of a vast system of wire ropes extending from a triple staging and since in both deposits the heavy minerals are more abundant of windlasses erected round the entire edge of the mine, which had by near the heads of the valleys in the plateau, it is also highly

probable this time become a huge open pit: the ropes from the upper windthat both have really been derived from the plateau deposit. In the lasses extended to the centre, and those from the lower tier to the latter, especially at São João da Chapada, the minerals accompany- sides of the pit: covering the whole mass like a gigantic

cobweb. ing the diamond are scarcely worn at all;

in the terraces and the river (See Plate II. fig. 12.) The buckets of blue ground were hauled up beds they are more worn and more abundant: the terraces, therefore, these ropes by means of horse whims, and in 1875 steam winding are to be regarded as a first concentration of the plateau material by engines began to be çmployed. By this time also improved methods the old rivers; and the cascalho as a second concentration by the in the treatment of the blue ground were introduced. It was carried modern rivers. The mining is carried on by negroes under the super off in carts to open spaces, where an exposure of some weeks to the air vision of overseer:: the cascalho is dug out in the dry season and was found to pulverize the hard rock far more efficiently than the removed to a higher level, and is afterwards washed out by hand in old method of crushing with mallets. The placer-miner's cradle and running water in shallow wooden basins (balras). The terraces can rocking-trough were replaced by puddling troughs stirred by be worked at all seasons, and the material is partly washed out revolying comb worked by horse power: reservoirs were constructed by leading streams on to it. The washing of the plateau material is for the scanty water-supply, bucket clevators were introduced to effected in reservoirs of rain water.

carry away the tailings; and the natives were confined in compounds It is difficult to obtain an estimate of the actual production of the For these improvements co-operation was necessary: the better Minas Geraes mines, for no oficial returns have been published, but claims, which in 1872 had risen from $100 to more than 14nos un is recent years it has certainly been rivalled by the yield in Bahia. value, began to be consolidated, and a Mining Board was introduced.

In a very few years, however, the open pit mining was rendered minerals found in the concentrates are pebbles and fragments of impossible by the mud rushes, by the falls of the masses of barren pyrope, zircon, cyanite, chrome-diopside, enstatite, a green pyroxene, rock known as "reef," which were left standing in the mine, and by mica, ilmenite, magnetite, chromite, hornblende, olivine, barytes, landslips from the sides, so that in 1883, when the pit had reached a calcite and pyrites. depth of about 400 ft., mining in the Kimberley crater had become In all the Ś. African mines the diamonds are not only crystals of almost impossible. By 1889, in the whole group of mines, Kimberley, various weights from fractions of a carat to 150 carats, but also occur Dutoitspan, De Beers and Bultfontein, open pit working was practi- as microscopic crystals disseminated through the blue ground. In cally abandoned. Meanwhile mining below the bottom of the pits by spite of this, however, the average yield in the profitable mines is means of shafts and underground tunnels had been commenced; but only from 0-2 carat to 0-6 carat per load of 1600 tb, or on an average the full development of modern methods dates from the year 1889 about I grs. per ton. The annual output of diamonds from the De when Cecil Rhodes and Alfred Beit, who had already secured control Beers mines was valued in 1906 at nearly £5,000,000; the value per of the De Beers mine, acquired also the control of the Kimberley mine, carat ranging from about 35s. to 70s. and shortly afterwards consolidated the entire group in the hands of Pipes similar to those which surround Kimberley have been found the De Beers Company. (See KIMBERLEY.)

in other parts of S. Africa. One of the best known is that of JagersThe scene of native mining was now transferred from the open pit fontein, which was really the first of the dry diggings (discovered in to underground tunnels; the vast network of wire ropes (Plate II. 1870). This large mine is near Fauresmith and 80 m. to the south fig. 12) with their ascending and descending buckets disappeared, and of Kimberley. In 1905 the year's production from the Orange River with it the cosmopolitan crowd of busy miners working like ants at Colony mines was more than 320,000 carats, valued at £938,000. But the bottom of the pit. In place of all this, the visitor to Kimberley | by far the largest of all the pipes hitherto discovered is the Premier encounters at the edge of the town only a huge crater, silent and apparently deserted, with no visible sign of the

SECTION OF KIMBERLEY MINE great mining operations which are conducted nearly half a mile below the surface. The aspect of the Kimberley due pit in 1906 is shown in fig. 13 of Plate II., which may be compared with the section of fig. 8.

altele In fig. 13, Plate II., the sequence of the basalt, shale and melaphyre is clearly visible on the sides of the pit; and

thelle net but fag. 8 shows how the crater or" pipe" of blue ground has

mot bolo penetrated these rocks and also the underlying quartzite. The workings at De Beers had extended into the still more deeply seated granite in 1906. Figure 9, Plate I., shows the top of the De Beers' crater with basalt over-10 lying the shale. Figure 8 also explains the modern system of mining introduced by Gardner Williams. A vertical shaft is sunk in the vicinity of the mine, and from this horizontal tunnels are driven into the pipe at different levels separated by intervals of 4oft. Through the blue ground itselí on each level a series of parallel tunnels about 120 ft. apart are driven to the opposite side of the pipe, and at right angles to these, and 36 ft. apart, another series of tunnels. When the tunnels reach the side of the mine they are opened upwards and sideways so as to form a large chamber, and the overlying mass of blue ground and debris is allowed to settle down and fill

చేసుండా up the gallery. On each level this process is carried somewhat farther back than on the level below (fig. 8); material is thus continually withdrawn from one side of the mine and extracted by means of the rock shaft on the opposite side, while the superincumbent débris is continwally unking, and is allowed to fall deeper on the side lart best from the shaft as the blue ground is withdrawn From Gardner Williamas's Diamond Mines of South Asrica. from beneath it. In 1905 the main shaft had been sunk

FIG. 8. to a depth of 2600 ft. at the Kimberley mine.

For the extraction and treatment of the blue ground the De Beers Company in its great winding and washing plant em mine in the Transvaal, about 300 m. to the east of Kimberley. This ploys labour-saving machinery on a gigantic scale. The ground is was discovered in 1902 and orrupics an area of about 75 acres. In transferred in trucks to the shaft where it is automatically

tipped into 1906 it was being

worked as a shallow open

mine; but the description skips hulling 96 cubic ft. (six truck loads); these are rapidly huisted of the Kimberley methods given above is applicable

to the washing to the surface, where their contents are automatically dumped into plant at that time being introduced into the Premier

mine upon a very side-tipping trucks, and these in turn are drawn away in a continual large scale. Comparatively few of the pipes which have been disprucession by an endless wire rope along the tram lines leading to the covered are at all rich in diamonds, and many are quite barren; some vaxt distributing floors." These are open tracts upon which the blue are filled with "hard blue" which even if diamantiferous may be BP"und is spread out and left exposed to sun and rain until it crumbles too cxpensive to work. and desintegrates, the process being hastened by harrowing with The most competent S. African geologists believe all these remarksean ploughs; this may require a period of three or six months, or ablc pigmes to be connected with volcanic outbursts which orcurred even a year. The stock of blue ground on the floors at one time in over the whole of S. Africa during the Cretaceous period (after the 1995 was nearly 4.500,ono loads The disintegrated ground is then deposition of the Stormberg beds), and drilled

these enormous craters brought back in the trucks and fed through perforated cylinders into through all the later formations. With the true pipes are associated the washing pans; the hard blue which has resisted disintegration dykes and fissurry also filled with diamantiferous blue ground. It on the floors, and the lumps which are too big to pass the cylindrical is only in the more northerly part of the country that the pipes weves, are crushed before going to the pans. These are shallow are filled with blur ground (ur" kimberlite "), and that they are Cylindrical troughs containing muddy water in which the diamonds diamantiferous; but over a great part of Cape Colony have been and other heavy minerals (concentrates) are surpt to the rim by discovered what are probably similar pipes filled with agglomerates, rev.lving toothed arms, while the lighter stuff escapes near the centre breccias and cuffs, and some with basic Luvas; one, in particular, in of the pan. The concentrates are then passed over sloping tables the Riversdale Divison near the southern coast, lucing occupied by a (pulsator) and shaken to and fro under a stream of water

which effects melilitc-bawal. It is quite clear that the occurrence of the diamond a second concentration of the heaviest material.

in the S. African pipes is quite different from the occurrences in L'atil recently the final separation of the diamond from the con- alluvial deposits which have been descrited above. The question of centrates was made by hani picking, but even this has now been the origin of the diamond in S. Africa and elsewhere is discussed replaced by machinery, owing to the remarkable discovery that a below. greased surface will hold a dumond while allowing the other heavy The River Digging on the Vaal river are still worked upon a small mimurals to pass over it. The concentrates are washed down a sloping scale, but the production from this wurce is nu limited that they are uble of corrugated iron which is smcard with grease, and it is found of little account in comparison with the mines in the blue ground. that practically all the diamonds adhere to the table, and the other The stones, however, are good; since they differ somewhat from the minerals are washed away. At the large and important Presnier mine Kimberley crystals it in probable that they were not derived from in the Tranwasl the Elmore proces used in British Columbia and the prescat piper. Another S. African locality must be mentioned; na Wales for the separation of metallic orus, has been also introdured considerable finds were reported in 1995 and 1906 from gravels In the Elmore prima wil is employed to fuat off the materials which at Semabula near Gwelo in Rhodesia where the diamond is associadhere to it. While the other materials remain

in the water, the oilated with chrysoberyl, curundum (wxh sapphire and ruby), topaz, being separated from the water by centrifugal action. The other garnet, ilmeníte, staurolite, rutile, with pebbles of quartz, granite. chlorite-schist, &c. Diamond has also been reported from kimberlite Beers group of pipes, were, however, certainly not the source of the pipes " in Rhodesia.

carbon at the Premier (Transvaal) mine, for at this locality the shales Oiher Localities. In addition to the South American localities do not exist. The view that the diamond

may have crystallized out mentioned above, small diamonds have also been mined since their from solution in its present matrix receives some support from the Ciscovery in 1890 on the river Mazaruni in British Guiana, and experiments of W. Luzi, who found that it can be corroded by the finds have been reported in the gold washings of Dutch Guiana. solvent action of fuseu blue ground; from the experiments of Borneo has possessed a diamond industry since the island was first J. Friedländer, who obtained diamond by dissolving graphite in fused settled by the Malays; the references in the works of Garcia de Orta, olivine; and still more from the experiments of R. von Hasslinger Linschoten, De Bout,'De Lact and others, to Malacca as a locality and J. Wolff, who have obtained it by dissolving graphite in a fused relate to Bornco. The large Borneo stone, over 360 carats in weight, mixture of silicates having approximately the composition of the known as the Matan, is in all probability not

a diamond. The chief blue ground. E. Cohen, who regarded the pipes as of the nature of a mines are situated on the river Kapuas in the west and near | mud volcano, and the blue ground as a kimberlite breccia altered by Bandjarmassin in the south cast of the island, and the alluvial hydrothermal action, thought that the diamond and accompanying deposits in which they occur are worked

by a small number of Chinese minerals had been brought up from deep-seated crystalline schists. and Malays. Australia

has yielded diamonds in alluvial deposits Other authors have sought the origin of the diamond in the action near Bathurst (where the first discovery was made in 1851) and of the hydrated magnesian silicates on hydrocarbons derived from Mudgee in New South Wales, and also near Bingara and Inverell bituminous schists, or in the decomposition of metallic carbides. in the north of the colony. At Mount Werong a stone weighing Of great scientific interest in this connexion is the discovery of 29 carats was found in 1905. At Ruby Hill near Bingara they were small diamonds in certain meteorites, both stones and irons; for found in a breccia filling a vulcanic pipe. At Ballina, in New England, example, in the stone which fell at Novo-l'rxi in Penza, Russia, in diamonds have been found in the sea sand. Other Australian 1886, in a stone found at Carcotc in Chile, and in the iron found at localities are Echunga in South Australia; Becchworth, Arena and Cañon Diablo in Arizona. Graphitic carbon in cubic torm (cliftonite) Melbourne in Victoria; Fremantle and Nullagine in Western has also been found in certain

meteoric" irons," for example in those Australia; the Palmer and Gilbert rivers in Queensland. These have from Magura in Szepes county, Hungary, and Youndegin near York been for the most part discoveries in alluvial deposits of the gold in Western Australia. The latter is now generally believed to be fields, and the stones were small. In Tasmania also diamonds have altered diamond. The fact that !!. Moissan has produced the been found in the Corinna goldfields. Europe has produced few diamond artificially, by allowing dissolved carbon to crystallize out diamonds. Humboldt searched for them in the Urals on account of at a hign temperature and pressure from molten iron, coupled with the similarity of the gold and platinum deposits to those of Brazil, the occurrence in meteoric iron, has led Sir William Crookes

and others and small diamonds were ultimately found (1829) in the gold washings to conclude that the mineral may have been derived from deep-seated of Bissersk, and later

at Ekaterinburg

and other spots in the Urals. iròn containing carbon in solution (see the article GEM, ARTIFICIAL). In Lapland they have been found in the sands of the Pasevig river, Adolf Knop suggested that this

may have first yielded hydrocarbons Siberia has yielded isolated diamonds from the gold washings of by contact with water, and that from those the crystalline diamond Yenisei. In North America a few small stones have been found in has

been formed. The meteoric occurrence has even

suggested the alluvial deposits, mostly auriferous, in Georgia, N. and S. Carolina, fanciful notion that all diamonds were originally derived from Kentucky, Virginia, Tennessee, Wisconsin, California, Oregon and meteorites. The meteoric iron of Arizona, some of which contains Indiana. 'A crystal weighing 238 carats was found in Virginia in diamond, is actually found

in and about a huge crater which is 1855, and one of 21 carats in Wisconsin in 1886. In 1906 a number supposed by some to have been formed by an immense meteorite of small diamonds were discovered in an altered peridotite some-penetrating the earth's crust. what resembling the S. African blue ground, at Murfreesboro, Pike It is, at any rate, established that carbon can crystallize as diamond county, Arkansas. Considerable interest attaches to the diamonds from solution in iron, and other metals; and it seems that high found in Wisconsin, Michigan and Ohio near the Great Lakes, for they temperature and pressure and the absence of oxidizing agents are are here found in the terminal moraines of the great glacial sheet which necessary conditions. The presence of sulphur, nickel, &c., in the is supposed to have spread southwards from the region of Hudson iron appears to favour the production of the diamond. On the other Bay; several of the drift minerals of the diamantifcrous region of hand, the occurrence in meteoric stones, and the experiments Indiana have been identified as probably of Canadian origin; no mentioned above, show that the diamond may also crystallize from diamonds have however yet been found in the intervening

country of a basic magma, capable of yielding

some of the

metallic oxides and Ontario. A rock similar to the blue ground of Kimberley has been ferro-magnesian silicates; a magma, therefore, which is not devoid found in the states of Kentucky and New York. The occurrence of of oxygen. This is still more forcibly suggested by the remarkable diamond in meteorites is described below.

cclogite boulder found in the blue ground of the Newlands mine, not Origin of the Dumond in Naturc.-It appears from the foregoing far from the Vaal river, and described by T. G. Bonney. The boulder account that at most localities the diamond is found in alluvial de- is a crystalline rock consisting of pyroxene (chromc-diopside), garnet, posits probably far from the place where it originated. The minerals and a little olivine, and is studdled with diamond crystals; a portion associated with it do not afford much clue to the original conditions; of it is preserved in the British Museum (Natural History). In they are mostly heavy minerals derived from the neighbouring rocks, another cclogitc boulder, diamond was found partly cmbedded in in which the diamond itself has not been observed. Among the pyrope. Similar boulders have also been found in the blue ground commonest associates of the diamond are quartz, topaz, tourmaline, ciscwhere. Specimens of pyrope with attached or embedded diamond rutile, zircon, magnetite, garnet, spinel and other minerals which are had previously been found in the blue ground of the De Beers mines. common accessory constituents of granite, gnciss and the crystalline In the Newlands boulder the diamonds have the appearance of being schists. Gold (also platinum) is a not infrequent associate, but this an original constituent of the cclogite. It seems therefore that a holomay only mean that the sands in which the diamond is found have crystalline pyroxene-garnet rock may be one source of the

diamond been searched because they were known to be auriferous; also that found in blue ground. On the other hand many tons of the somewliat both gold and diamond are among the most durable of minerals

and similar
cclogite in the De Beers mine have been crushed and

have not may have survived from ancient rocks of which other traces have been yielded diamond. Further, the ilmenite, which is the most character lost.

istic associate of the diamond in blue ground, and other of the The localities at which the diamond has been supposed to occur accompanying minerals, may have come from basic rocks of a in its original matrix are the following:-at Wajra Karur, in the different nature. Cuddapah district, India, M. Chaper found diamond with corundum The Inverell occurrence may prove to be another example of in a decomposed red pegmatite vein in gneiss. At São João da diamond crystallized from a basic rock. Chapada, in Minas Geraes, diamonds occur in a clay interstratified In both occurrences, however, there is still the possibility that the with the itacolumite, and are accompanied by sharp

crystals of rutile eclogite or the baxalt is not the original matrix, but may have caught and hacmatite in the neighl»ourhood of decomposed quartz veins up the already formed diamond from some other matrix. Some which intersect the itacolumite. It has been suggested that these regard the cclogite boulders as derived from deep-seated crystalline three minerals were originally formed in the quartz veins. In both rocks, others as concretions in the blue ground.. these occurrences the evidence is certainly not sufficient

to establish None of the inclusions in the diamond gives any clue to its origin; the presence of an original matrix. At Inverell in New South

Wales diamond itself has been found as an inclusion, as have also black a diamond (1906) has been found embedded in a hornblende diabasc specks of some carbonaccous materials. Other black specks have been which is described as a dyke intersecting the granite. Finally there is identified as haematite and ilmenite; gold has also been found; the remarkable occurrence in the blue ground of the African pipes. other included minerals recorded are rutile, topaz, quartz, Pyrites,

There has been much controversy concerning the nature and origin apophyllite, and green scales of chlorite (?). Some of these are of very of the blue ground itself; and cven granted that (as is generally doubtful identification; others (e.g. apophyllite and chlorite) may believed) the blue ground is a much serpentinized volcanic breccia have been introduced along cracks. Some of the fibrous inclusions consisting originally of an olivine-bronzite-bintite rock (the so-called were identified by H. R. Göppert as vegetable structures and were kimberlite), it contains so many rounded and angular fragments of supposed to point to an organic origin, but this view is no longer held. various rocks and minerals that it is difficult to say which of them Liquid inclusions, some of which are certainly carbon dioxide, have may have belonged to the original rock,

and whether any were formed also been oberved. in situ, or were brought up from below as inclusions. Carvill Lewis Finally, then, both experiment and the natural occurrence in rocks believed the blue ground to be true eruptive rock, and the carbon to and meteorites suggest that diamond may crystallize not only from have been derived from the bituminous shales of which it contains iron but also from a basic silicate magma, possibly from various rocks fragments. The Kimberley shales, which are penetrated by the De consisting of basic silicates. The blue ground of S. Africa may be the result of the serpentinization of several such rocks, and although the shah of Persia. Another stone, the Taj-e-mah, belonging to now both brecciated and serpentinized some of these may have been the shah, is a pale rose pear-shaped stone and is said to weigh this view is the fact that the diamonds in one pipe generally differ 146 carats. somewhat in character from those of another, ever though ihey be Other famous Indian diamonds are the following:- The Sancy, Dear neighbours.

weighing 53 18 carats, which is said to have been successively the History.-All the famous diamonds of antiquity must have been property of Charles the Bold, de Sancy, Queen Elizabeth, Indian stones. The first author who described the Indian mines Henrietta Maria, Cardinal Mazarin, Louis XIV.; to have been at all fully was the Portuguese, Garcia de Orta (1565), who was stolen with the Pitt during the French Revolution; and subsephysician to the viceroy of Goa. Before that time there were quently to have been the property of the king of Spain, Prince only_legendary accounts like that of Sindbad's “Valley of Demidoff and an Indian prince. The Nassak, 788 carats, the Ebe Diamonds," or the tale of the stones found in the brains of property of the duke of Westminster. The Empress Eugénie, serpents. V. Ball thinks that the former legend originated in the 51 carats, the property of the gaikwar of Baroda. The Pigoll, Indian practice of sacrificing cattle to the evil spirits when a new 49 carats (?), which cannot now be traced. The Pusha, 40 carats. mine is opened; birds of prey would naturally carry off the desh, The White Saxon, 48 carats. The Star of Este, 25lt carats. and might give rise to the tale of the cagles carrying diamonds

Coloured Indian diamonds of large size are rare; the most adhering to the meat.

famous are:-a beautiful blue brilliant, 6714 carats, cut from a The following are some of the most famous diamonds of the stone weighing 11216 carats brought to Europe by Tavernier. world:

It was stolen from the French crown jewels with the Regent and A large stone found in the Golconda mines and said to have was never recovered. The Hope, 44 carats, has the same colour weighed 787 carats in the rough, before being cut by a Venetian and is probably a portion of the missing stone: it was so-called lapidary, was seen in the treasury of Aurangzeb in 1665 by as forming part of the colection of il. T. Hope bought for Tavernier, who estimated its weight after cutting as 280 (1) 1.18,000), and was sold again in 1906 (resold 1909). Two other carats, and described it as a rounded rose-cut-stone, tall on one bluc diamonds are known, weighing 13; and 1 carats, which may side. The name Great Mogul has been frequently applied to this also be portions of the French diamond. The Dresden Green, one stone. Tavernier states that it was the famous stone given to of the Saxon crown jewels, 40 carats, has a fine apple-green Shah Jahan by the emir Jumla. The Orlof, stolen by a French colour. The Florentine, 1335 carats, one of the Austrian crown soldier from the cye of an idol in a Brahmin temple, stolen again jewels, is a very pale yellow. from him by a ship's captain, was bought by Prince Orloff for

The most famous Brazilian stones are::- The Star of the South, £90,000, and given to the empress Catharine II. It weighs found in 1853, when it weighed 254) carats and was sold for 1941 carats, is of a somewhat yellow tirse, and is among ihe £40,000; when cut it weighed 125 carats and was bought by the Russian crown jewels. The Koh-i-nor, which was in 1739 in the gaik war of Barocla for £80,000. Also a diamond belonging to possession of Nadir Shah, the Persian conqueror, : r.d in 1813 in Mr Dresden, 119 carats before, and 765 carats after cutting. that of the raja of Lahore, passed into the hands of the East Many large stones have been found in South Africa; some are India Company and was by them presented to Queen Victoria yellow but some are as colourless as the best Indian or Brazilian in 1850. It then weighed 1861'a carats, but was recut: London stones. The most famous are the following:--the Star of South by Amsterdam workmen, and now weighs 106,' carats. There Ajrier, or Dudley, mentioned alve, 83! carats rough, 46, carats Las been much discussion concerning the possibility of this stone cut. The Skuurl, 288 carats rough, 120 carats cut. Both these and the Orloff being both fragments of the Great Mogul. The were found in the river diggings. The Porker Rhodes from Mogul Baber in his memoirs (1526) relates how in his conquest of Kimberley of the finest water, ucighed about 150 carats. The lastia he captured at Agra the great stone wcighing 8 mishi.als, Picturis, 180 carats, was cut from an octahedron weighing 4571 or 320 ratis, which may be equivalent to about 18 carats. The carats, and was sold to the nium of Hyderabad for £400,000. Koh-inor has been identificd by some authors with this stone and The Tilluny, a magnificent orange yellow stone, weighs 1251 by others with the stone scen by Tavernier. Tavernier, however, carats cut. A yellowish octahedron jound at I)e Beers weighed subsequently described and sketched the diamont which he saw 428 carats, anil yielded a brilliant of 288 carats. Some of the as shaped like a bisected egg, quite different therefore from the finest and largest stones have come from the Jugersfontein mine; Koh-i-nor. Nevil Story Maskelync has shown reason for belicv- one, the Jubilee, found in 1895. wcighed 6.40 carts in the rough ing that the stone which Tavernier saw was really the Koh-i-nor and 239 carats when cut. lntil 1905 the lirgest known diamond and that it is identical with the great diamond of Babyer; and in the world was the Exuelsior, found in 1 M03 at Jagersfontein by that the 280 carats of Tavernier is a misinterpretation on his part a native while loading a truck. It wrighed 0.1 carats, and was of the Indian weights. He suggests that the other and larger ultimately cut into ten stunes weighing from 3 to 13 carats. diamond of antiquity which was given to Shah Jahan mily But all previous records were surpassed in 1965 by a magnificent be one which is now in the treasury of Teheran, and that this is stone more than three times the size of any known diamond, the true Great Mogul which was confused by Tavernier with the which was found in the yellow ground at the nruly discovered one he saw. (Sce BullAppendix I. to Tavernier's Trutels (1886); Premier mine in the Transvaal. Thus extraordinary diamond and Maskelyne, Valurc, 1891, 44. P. 555).

weighed 30:57 carats (1) Ib) and was clear and water white; the The Regent or Pilt diamond is a magnificent stone found in lart of its surfu es aproared to be a cleavage plane, so that it either India or Burnco; it weighed sto carats and was bought for might be only a portion of a much larger stone. It was known 4:0.100 by Pitt, the governor of Madras; it was subsequently, as the Cullinin Dimond. This stone was pure hoved by the in 1;1;, bought fur (10,000 for, according to some authorities, Transvaal government in 193; and presented to King Edward VII. (135.000) by the duke of Orleans, refent of France; it was re- It w.sunt to Imsterdam to facut, and in 19 w.sitiviele into C.co by cutting to 13614 carats; was stole with the her crown nine large stones and a number of moll brilliants. The four jesels during the Revolution, but was recovered and is still in lrg of stones weigh 510}rals, pro carats.o2 carats and 02 France. The Albur Shikwis originally a stone of 116 carats with car.its respectively. Of these the first and second are the largest Aralric inscriptions engraved up in it; after lving cut down to brilliants in existence. All the stunts are flawless and of the ;I carts it was bought by the gaikwar of Baronia fur £35.000. finest quality. The Sisim, now in the wine wion of the r.izan of Hyderabad, is hift); D. Julipie

S7... on Duimnas ! Truls

Bin X. APRY-Bewtir de But, Grmn.grumat lapidum Sloped to weigh 277 carats, but it is only a portion of a stone (1757: J. Nise, In 19:12 ]??... Real 11-12); Troleren hith is id to have wrighred 4.49 carats liefore it was broken. DE:". Per. I 1910 1929). The Great Tolle, a rectangular stone soenly T..verrier in 193: Wurs..!!1m printer Sie. Die!":"1-31;(.7. nnner. a: Gulconda, was found by him to weigh 24 16 carats; Mashelyre P4.nr: 19:Ashral Fobietunde snorJeon regan's it as identical with the Dryu 1-sur, which is also a

anil.. (!........ ( m.,,Wall, bu rectangular stone weighing about 186 carals in the possession of of India (1081);C. W. Ring The Surullliswey Picus Stones

II. inurl :: and